commit b8e0960de41be52b3e6c85f08fdc722925c70941
author scroggo <scroggo@chromium.org> Tue Apr 12 07:41:22 2016 -0700
committer Commit bot <commit-bot@chromium.org> Tue Apr 12 07:41:22 2016 -0700
tree 3107dcb1dbb04574321c079f54d5ee36a81ee479
parent 37798fbd82a7d064c5cc1516f120546a3408044b

Make is_ktx safer

Rather than assuming the data passed to ktx at least
KTX_FILE_IDENTIFIER_SIZE, pass the length of the data to is_ktx and
compare it.

Splitting off from crrev.com/1862133002, which no longer depends on
is_ktx.
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1882593002

Review URL: https://codereview.chromium.org/1882593002

src/gpu/SkGr.cpp

diff --git a/src/gpu/SkGr.cpp b/src/gpu/SkGr.cpp
index 7169091..84023ec 100644
--- a/src/gpu/SkGr.cpp
+++ b/src/gpu/SkGr.cpp
@@ -87,7 +87,7 @@
 
         *outStartOfDataToUpload = bytes + ETC_PKM_HEADER_SIZE;
         return kETC1_GrPixelConfig;
-    } else if (SkKTXFile::is_ktx(bytes)) {
+    } else if (SkKTXFile::is_ktx(bytes, data->size())) {
         SkKTXFile ktx(data);
 
         // Is it actually an ETC1 texture?